The Berlin Wall that came down 20 years ago this month was an apt symbol of communism. It represented a historically unprecedented effort to prevent people from “voting with their feet” and leaving a society they rejected.

Supporters of the climate bill passed by the House and the similar bill under consideration in the Senate — including President Obama and Democratic congressional leaders — say that the cap-and-trade approach would guarantee greenhouse-gas reductions.

A reader recently challenged us to explain what he sees as a contradiction in our editorial positions. We support the goal of universal health care, but argue that President Obama must keep his pledge not to pay for it with borrowed money.

Here is the good news on the climate front: The Europeans have ratcheted down their emissions targets, the Chinese are getting serious about solar power and energy efficiency, and Washington is lumbering toward a carbon cap.

Iran's expanding nuclear program poses one of the Obama administration's most vexing foreign policy challenges. Fortunately, the conditions for containing Tehran's efforts may be better today than they have been in years.